Compressors are widely used in industrial and commercial operations. For example, a typical commercial gas turbine used to generate electrical power includes an inlet section, a compressor section downstream from the inlet section, a combustion section downstream from the compressor section, a turbine section downstream from the combustion section, and an exhaust section downstream from the turbine section. The inlet section purifies and otherwise conditions a working fluid (e.g., air) that flows into the compressor section. The compressor section produces a compressed working fluid that flows to the combustion section where it mixes with fuel before combusting to produce combustion gases having a high temperature and pressure. The combustion gases flow through the turbine section to produce work, and the exhaust section purifies and otherwise conditions the combustion gases prior to further use and/or discharge to the environment.
FIG. 1 provides a perspective view of an exemplary prior art compressor 10, and FIG. 2 provides a side cross-section view of the exemplary compressor 10 shown in FIG. 1. As shown in FIGS. 1 and 2, a casing 12 generally surrounds the compressor 10 to contain a working fluid (e.g., air), and a portion of the casing 12 has been removed in FIG. 1 to expose the components inside the compressor 10. Alternating stages of rotating blades 14 and stator vanes 16 inside the casing 12 progressively impart kinetic energy to the working fluid to produce a compressed working fluid at a highly energized state. Each rotating blade 14 may be circumferentially arranged around a rotor wheel 18 to extend radially outward toward the casing 12. Conversely, each stator vane 16 may be circumferentially arranged around the casing 12 to extend radially inward toward a spacer wheel 20 that separates adjacent stages of rotating blades 14.
Compressed working fluid that leaks around or bypasses the stator vanes 16 reduces the efficiency of the compressor 10. As a result, some compressors may include inner shroud segments or fairing segments to reduce the amount of compressed working fluid that flows between the stator vanes 16 and the spacer wheel 20. For example, as shown most clearly in FIG. 2, the spacer wheels 20 radially inward from the stator vanes 16 may include circumferential dovetail slots 22 adapted to receive T-shaped fairing segments 24. The circumferential dovetail slots 22 radially restrain the T-shaped fairing segments 24, and the T-shaped fairing segments 24 include a surface 26 that generally conforms to an inner tip 28 of the stator vanes 16 to reduce leakage between the stator vanes 16 and the spacer wheels 20. Although the T-shaped fairing segments 24 are effective at reducing leakage between the stator vanes 16 and the spacer wheels 20, the circumferential dovetail slots 22 in the spacer wheels 20 may reduce the high cycle fatigue limit of the spacer wheels 20. As a result, an improved fairing segment that does not require slots in the spacer wheels would be useful.